Semiconductor device

ABSTRACT

A semiconductor device includes a substrate, a first fin, and a second fin. The first and second fins are spaced apart from each other in a first direction on the substrate and extend in a second direction intersecting the first direction. The semiconductor device further includes a first shallow trench formed between the first and second fins, and a field insulating film which fills at least a part of the first shallow trench. The field insulating film includes a first portion, a second portion adjacent to the first portion, and a third portion adjacent to the second portion and adjacent to a side wall of the first shallow trench. The first portion includes a central portion of an upper surface of the field insulating film in the first direction. The upper surface of the field insulating film is in a shape of a brace recessed toward the substrate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119 to Korean PatentApplication No. 10-2019-0040756, filed on Apr. 8, 2019, and KoreanPatent Application No. 10-2019-0109469, filed on Sep. 4, 2019, in theKorean Intellectual Property Office, the disclosures of which areincorporated by reference herein in their entireties.

TECHNICAL FIELD

Exemplary embodiments of the present inventive concept relate to asemiconductor device, and more particularly, to a semiconductor deviceincluding a shallow trench isolation (STI) region filled using an atomiclayer deposition (ALD) method.

DISCUSSION OF THE RELATED ART

A semiconductor device may include an integrated circuit including aplurality of metal oxide semiconductor field effect transistors(MOSFETs). As the size and the design rule of such a semiconductordevice are gradually reduced, the MOSFETs are scaled down. This scalingdown may cause a short channel effect, which may degrade the operatingcharacteristics of the semiconductor device. Thus, various methods forforming a semiconductor device having excellent performancecharacteristics, high reliability and low power consumption are beingstudied, while overcoming the limitations associated with the highintegration level of the semiconductor device.

SUMMARY

Aspects of the present inventive concept provide a semiconductor devicewith improved operating characteristics.

Aspects of the present inventive concept also provide a semiconductordevice in which a manufacturing process is simplified.

According to exemplary embodiments of the present inventive concept, asemiconductor device includes a substrate, a first fin, and a secondfin. The first and second fins are spaced apart from each other in afirst direction on the substrate and extend in a second directionintersecting the first direction. The semiconductor device furtherincludes a first shallow trench formed between the first and secondfins, and a field insulating film which fills at least a part of thefirst shallow trench. The field insulating film includes a firstportion, a second portion adjacent to the first portion, and a thirdportion adjacent to the second portion and adjacent to a side wall ofthe first shallow trench. The first portion includes a central portionof an upper surface of the field insulating film in the first direction.The upper surface of the field insulating film is in a shape of a bracerecessed toward the substrate.

According to exemplary embodiments of the present inventive concept, asemiconductor device includes a substrate, a first fin, and a secondfin. The first and second fins are spaced apart from each other in afirst direction on the substrate and extend in a second directionintersecting the first direction. The semiconductor device furtherincludes a first shallow trench formed between the first and secondfins, and a field insulating film which fills at least a part of thefirst shallow trench. An upper surface of the field insulating filmincludes a first portion, a second portion and a third portionsequentially located from a center of the shallow trench in the firstdirection. A first slope formed by the first portion with the firstdirection is greater than a second slope formed by the second portionwith the first direction, and a third slope formed by the third portionwith the first direction is greater than the second slope. Signs of thefirst, second and third slopes are the same.

According to exemplary embodiments of the present inventive concept, asemiconductor device includes a substrate, a first fin, and a secondfin. The first and second fins are spaced apart from each other in afirst direction on the substrate and extend in a second directionintersecting the first direction. The semiconductor device furtherincludes a shallow trench formed between the first and second fins, anda field insulating film which fills at least a part of the shallowtrench. An upper surface of the field insulating film is in a shapehaving an inflection point.

According to exemplary embodiments of the present inventive concept, asemiconductor device includes a substrate, a first shallow trenchdisposed in a first region of the substrate, a first lower patterndisposed in the first region of the substrate and extending in a firstdirection, and a second lower pattern disposed in the first region ofthe substrate and extending in the first direction. The first and secondlower patterns are separated by the first shallow trench, and the firstshallow trench has a first width in a second direction. Thesemiconductor device further includes a second shallow trench disposedin a second region of the substrate, a third lower pattern disposed inthe second region of the substrate and extending in a third direction,and a fourth lower pattern disposed in the second region of thesubstrate and extending in the third direction. The third and fourthlower patterns are separated by the second shallow trench, and thesecond shallow trench has a second width in a fourth direction which isgreater than the first width. The semiconductor device further includesa first field insulating film which fills at least a part of the firstshallow trench, and a second field insulating film which fills at leasta part of the second shallow trench. An upper surface of the first fieldinsulating film includes a first portion adjacent to the first lowerpattern, and a second portion adjacent to the second lower pattern. Aslope of the first portion of the upper surface of the first fieldinsulating film decreases as it extends away from the first lowerpattern. A slope of the second portion of the upper surface of the firstfield insulating film decreases as it extends away from the second lowerpattern. An upper surface of the second field insulating film includes athird portion, and a fourth portion and a fifth portion disposed on bothsides of the third portion. A slope of the third portion of the uppersurface of the second field insulating film is constant. A slope of thefourth portion of the upper surface of the second field insulating filmdecreases as it extends away from the third lower pattern. A slope ofthe fifth portion of the upper surface of the second field insulatingfilm decreases as it extends away from the fourth lower pattern.

According to exemplary embodiments of the present inventive concept, asemiconductor device includes a substrate, a first shallow trenchdisposed in a first region of the substrate, a first lower patterndisposed in the first region of the substrate and extending in a firstdirection, and a second lower pattern disposed in the first region ofthe substrate and extending in the first direction. The first and secondlower patterns are separated by the first shallow trench, and the firstshallow trench has a first width in a second direction. Thesemiconductor device further includes a second shallow trench disposedin a second region of the substrate, a third lower pattern disposed inthe second region of the substrate and extending in a third direction,and a fourth lower pattern disposed in the second region of thesubstrate and extending in the third direction. The third and fourthlower patterns are separated by the second shallow trench, and thesecond shallow trench has a second width in a fourth direction which issmaller than the first width. The semiconductor device further includesa first field insulating film which fills at least a part of the firstshallow trench, and a second field insulating film which fills at leasta part of the second shallow trench. The first field insulating filmincludes at least one or more separation layers disposed in the firstfield insulating film and extending alongside an upper surface of thesubstrate.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects and features of the present inventiveconcept will become more apparent by describing in detail exemplaryembodiments thereof with reference to the accompanying drawings, inwhich:

FIG. 1 is a layout view illustrating a semiconductor device according toexemplary embodiments of the present inventive concept.

FIG. 2 is a cross-sectional view taken along line A-A′ of FIG. 1according to exemplary embodiments of the present inventive concept.

FIG. 3 is an enlarged view of region X of FIG. 2 according to exemplaryembodiments of the present inventive concept.

FIG. 4 is an enlarged view of region Y of FIG. 3 according to exemplaryembodiments of the present inventive concept.

FIGS. 5 and 6 are cross-sectional views taken along line B-B′ of FIG. 3according to exemplary embodiments of the present inventive concept.

FIG. 7 is a cross-sectional view taken along lines C-C′ and D-D′ of FIG.1 according to exemplary embodiments of the present inventive concept.

FIG. 8 is a cross-sectional view illustrating a semiconductor deviceaccording to exemplary embodiments of the present inventive concept.

FIG. 9 is a cross-sectional view illustrating a semiconductor deviceaccording to exemplary embodiments of the present inventive concept.

FIG. 10 is a cross-sectional view illustrating a semiconductor deviceaccording to exemplary embodiments of the present inventive concept.

FIG. 11 is a layout diagram illustrating a semiconductor deviceaccording to exemplary embodiments of the present inventive concept.

FIG. 12 is a cross-sectional view taken along line E-E′ of FIG. 11according to exemplary embodiments of the present inventive concept.

FIGS. 13 to 21 are intermediate stage diagrams illustrating a method formanufacturing a semiconductor device according to exemplary embodimentsof the present inventive concept.

FIGS. 22 to 28 are diagrams provided to describe a semiconductor deviceaccording to exemplary embodiments of the present inventive concept.

FIG. 29 is a diagram provided to describe a semiconductor deviceaccording to exemplary embodiments of the present inventive concept.

FIGS. 30 and 31 are diagrams provided to describe a semiconductor deviceaccording to exemplary embodiments of the present inventive concept.

FIGS. 32 and 33 are diagrams provided to describe a semiconductor deviceaccording to exemplary embodiments of the present inventive concept.

FIGS. 34 and 35 are diagrams provided to describe a semiconductor deviceaccording to exemplary embodiments of the present inventive concept.

FIGS. 36 to 40 are intermediate stage diagrams provided to describe amethod for manufacturing a semiconductor device according to exemplaryembodiments of the present inventive concept.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Exemplary embodiments of the present inventive concept will be describedmore fully hereinafter with reference to the accompanying drawings. Likereference numerals may refer to like elements throughout theaccompanying drawings.

It will be understood that the terms “first,” “second,” “third,” etc.are used herein to distinguish one element from another, and theelements are not limited by these terms. Thus, a “first” element in anexemplary embodiment may be described as a “second” element in anotherexemplary embodiment.

It should be understood that descriptions of features or aspects withineach exemplary embodiment should typically be considered as availablefor other similar features or aspects in other exemplary embodiments,unless the context clearly indicates otherwise.

As used herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise.

Spatially relative terms, such as “beneath”, “below”, “lower”, “under”,“above”, “upper”, etc., may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” or“under” other elements or features would then be oriented “above” theother elements or features. Thus, the exemplary terms “below” and“under” can encompass both an orientation of above and below.

It should be understood that when a component, such as a film, a region,a layer, or an element, is referred to as being “on”, “connected to”,“coupled to”, or “adjacent to” another component, it can be directly on,connected, coupled, or adjacent to the other component, or interveningcomponents may be present. It will also be understood that when acomponent is referred to as being “between” two components, it can bethe only component between the two components, or one or moreintervening components may also be present. Other words used to describethe relationship between elements should be interpreted in a likefashion.

Herein, when two or more elements or values are described as beingsubstantially the same as or about equal to each other, it is to beunderstood that the elements or values are identical to each other,indistinguishable from each other, or distinguishable from each otherbut functionally the same as each other as would be understood by aperson having ordinary skill in the art. It will be further understoodthat when two components or directions are described as extendingsubstantially parallel or perpendicular to each other, the twocomponents or directions extend exactly parallel or perpendicular toeach other, or extend approximately parallel or perpendicular to eachother within a measurement error as would be understood by a personhaving ordinary skill in the art. Further, it is to be understood thatwhile parameters may be described herein as having “about” a certainvalue, according to exemplary embodiments, the parameter may be exactlythe certain value or approximately the certain value within ameasurement error as would be understood by a person having ordinaryskill in the art.

Hereinafter, a semiconductor device according to exemplary embodimentsof the present inventive concept will be described with reference toFIGS. 1 to 7.

FIG. 1 is a layout view illustrating a semiconductor device according toexemplary embodiments of the present inventive concept. FIG. 2 is across-sectional view taken along line A-A′ of FIG. 1 according toexemplary embodiments of the present inventive concept. FIG. 3 is anenlarged view of region X of FIG. 2 according to exemplary embodimentsof the present inventive concept. FIG. 4 is an enlarged view of region Yof FIG. 3 according to exemplary embodiments of the present inventiveconcept. FIGS. 5 and 6 are cross-sectional views taken along line B-B′of FIG. 3 according to exemplary embodiments of the present inventiveconcept. FIG. 7 is a cross-sectional view taken along lines C-C′ andD-D′ of FIG. 1 according to exemplary embodiments of the presentinventive concept.

Referring to FIGS. 1 to 5, a semiconductor device according to exemplaryembodiments of the present inventive concept includes a substrate 100,first, second and third fins F1, F2 and F3, a shallow trench ST1, afield insulating film 200, a source/drain 310, a first interlayerinsulating film 300, a silicide 330, a contact 350, and a secondinterlayer insulating film 500.

A first direction D1 may be any one direction in a horizontal direction.A second direction D2 may be a direction intersecting the firstdirection D1, for example, a direction substantially perpendicular tothe first direction D1. A third direction D3 may be a directionintersecting both the first direction D1 and the second direction D2.For example, the third direction D3 may be a direction substantiallyperpendicular to both the first direction D1 and the second directionD2. In this case, the first direction D1 and the second direction D2 maybe horizontal directions substantially perpendicular to each other, andthe third direction D3 may be a vertical direction. For example, thefirst direction D1, the second direction D2 and the third direction D3may be directions orthogonal to one another.

The substrate 100 may be made of one or more semiconductor materialsincluding, for example, Si, Ge, SiGe, GaP, GaAs, SiC, SiGeC, InAs andInP. Alternatively, a silicon on insulator (SOI) substrate may be used.

The first, second and third fins F1, F2 and F3 may extend in the seconddirection D2 and may be spaced apart from each other in the firstdirection D1. The first, second and third fins F1, F2 and F3 may besequentially disposed in the first direction D1. For example, the secondfin F2 may be located between the first fin F1 and the third fin F3.

Although the exemplary embodiments described herein include three finsF1, F2 and F3, exemplary embodiments of the present inventive conceptare not limited thereto. For example, according to exemplaryembodiments, a different number of fins may be included.

The first, second and third fins F1, F2 and F3 may include some parts ofthe substrate 100, and may include an epitaxial layer grown from thesubstrate 100. The first, second and third fins F1, F2 and F3 mayinclude, for example, Si, SiGe, etc.

The first, second and third fins F1, F2 and F3 may include compoundsemiconductors, and may include, for example, group IV-IV compoundsemiconductors or group III-V compound semiconductors.

For example, taking the group IV-IV compound semiconductor as anexample, the first, second and third fins F1, F2 and F3 may be a binarycompound or a ternary compound containing at least two or more amongcarbon (C), silicon (Si), germanium (Ge) and tin (Sn), or a compoundobtained by doping these elements with a group IV element.

Taking the group III-V compound semiconductor as an example, the first,second and third fins F1, F2 and F3 may be any one of a binary compound,a ternary compound, and a quaternary compound formed by combining atleast one of aluminum (Al), gallium (Ga) and indium (In) as group IIIelements with one of phosphorus (P), arsenic (As), and antimony (Sb) asgroup V elements.

In the semiconductor device according to the exemplary embodimentsdescribed herein, the first, second and third fins F1, F2 and F3 will bedescribed as including silicon. However, exemplary embodiments of thepresent inventive concept are not limited thereto.

The shallow trench ST1 may be formed on side surfaces of the first,second, and third fins F1, F2, and F3 in the first direction D1,respectively. For example, the shallow trench ST1 may be formed betweenthe first and second fins F1 and F2, and the shallow trench ST1 may beformed between the second and third fins F2 and F3. For example, theshallow trenches ST1 formed between the first, second and third fins F1,F2 and F3 may be formed in the same manner. However, exemplaryembodiments of the present inventive concept are not limited thereto,and the shallow trenches may be implemented differently from each otherwhen being formed.

The field insulating film 200 may fill the shallow trench ST1. The fieldinsulating film 200 may expose some of the upper parts and the sidesurfaces of the first, second and third fins F1, F2 and F3.

The field insulating film 200 may include, for example, at least one ofsilicon oxide, silicon nitride, silicon oxynitride, and a low dielectricconstant material having a dielectric constant lower than that ofsilicon oxide. The low dielectric constant material may include, but isnot limited to, for example, Flowable Oxide (FOX), Tonen SilaZene(TOSZ), Undoped Silica Glass (USG), Borosilica Glass (BSG),PhosphoSilica Glass (PSG), BoroPhosphoSilica Glass (BPSG), PlasmaEnhanced Tetra Ethyl Ortho Silicate (PETEOS), Fluoride Silicate Glass(FSG), Carbon Doped Silicon Oxide (CDO), Xerogel, Aerogel, AmorphousFluorinated Carbon, Organo Silicate Glass (OSG), Parylene,bis-benzocyclobutenes (BCB), SiLK, polyimide, porous polymeric materialor combinations thereof.

The field insulating film 200 may include a material that applies stressto the first, second and third fins F1, F2 and F3. If the fieldinsulating film 200 applies stress to the channels of the transistorsformed on the first, second and third fins F1, F2 and F3, the mobilityof electrons or holes which are carriers may be improved.

A gate electrode 420 extends in the first direction D1, and may bedisposed on the first, second and third fins F1, F2 and F3 to intersecteach of the first, second and third fins F1, F2 and F3.

A gate insulating film 410 may include an interface film including asilicon oxide film, and a high dielectric constant film including a highdielectric constant material. The high dielectric constant film mayinclude a high dielectric constant material having a dielectric constanthigher than that of the silicon oxide film. The high dielectric constantmaterial may include, but is not limited to, for example, one or more ofsilicon oxynitride, silicon nitride, hafnium oxide, hafnium siliconoxide, lanthanum oxide, lanthanum aluminum oxide, zirconium oxide,zirconium silicon oxide, tantalum oxide, titanium oxide, bariumstrontium titanium oxide, barium titanium oxide, strontium titaniumoxide, yttrium oxide, aluminum oxide, lead scandium tantalum oxide orlead zinc niobate.

The high dielectric constant film may include a dipole-forming materialto adjust a threshold voltage of the gate electrode 420. Thedipole-forming material may be at least one of, for example, La, Nd, Eu,Dy, Ho, and Yb. However, the dipole-forming material is not limitedthereto.

The gate electrode 420 may include a first conductive film and a secondconductive film. The second conductive film may be formed on the gateinsulating film 410. The first conductive film may include an n-type orp-type work function regulator. The work function regulator may include,for example, at least one of TiN, TaN, and TiAlC. However, exemplaryembodiments of the present inventive concept are not limited thereto.The first conductive film may be formed on the second conductive film.The second conductive film may include, but is not limited to, at leastone of W and TiN.

A spacer film 430 may be formed on both sides of the gate electrode 420.Although the spacer film 430 is illustrated as being a single film,exemplary embodiments of the present inventive concept are not limitedthereto. For example, in exemplary embodiments, the spacer film 430 maybe a multi-film formed by stacking a plurality of films. The shapes ofeach of the multi-spacers forming the spacer film 430 may be, forexample, an I-shape or an L-shape or a combination thereof, depending onthe manufacturing process or the application. The spacer film 430 mayinclude, for example, at least one of silicon nitride (SiN), siliconoxynitride (SiON), silicon oxide (SiO2), silicon oxycarbonitride(SiOCN), and a combination thereof.

A source/drain 310 may be disposed on both sides of the gate electrode420. The source/drain 310 may include an epitaxial layer formed by anepitaxial process. The source/drain 310 may be an elevated source/drain.When the source/drain 310 is an n-type transistor, it may include, forexample, a Si epitaxial layer or a SiC epitaxial layer. The source/drain310 may include, for example, SiP or SIPC with P doped at a highconcentration. Alternatively, when the source/drain 310 is a p-typetransistor, it may include, for example, a SiGe epitaxial layer.

An outer peripheral surface of the source/drain 310 may be at least oneof, for example, a diamond shape, a circular shape and a rectangularshape. FIG. 2 exemplarily illustrates a diamond shape (or a pentagonalshape or a hexagonal shape).

The first interlayer insulating film 300 may cover the upper surfaces ofthe substrate 100 (or the first to third fins F1, F2 and F3), thesource/drain 310 and the field insulating film 200. The first interlayerinsulating film 300 may fill the space of the side surfaces of the gateelectrodes 420 and the dummy gate electrodes. The upper surface of thefirst interlayer insulating film 300 may form the same plane as theupper surface of the spacer film 430.

A second interlayer insulating film 500 may be formed on the firstinterlayer insulating film 300. Each of the first interlayer insulatingfilm 300 and the second interlayer insulating film 500 may include, forexample, at least one of silicon oxide, silicon nitride, siliconoxynitride and a low dielectric constant material having a dielectricconstant lower than that of silicon oxide.

A contact 350 may penetrate the first interlayer insulating film 300 andthe second interlayer insulating film 500 to be in contact with thesource/drain 310. The contact 350 may be deeper than the upper surfaceof the source/drain 310. The source/drain 310 may form a silicide 330 atan interface with the contact 350. The contact 350 may include, forexample, barrier metal on the surface being in contact with the firstinterlayer insulating film 300, the second interlayer insulating film500, and the source/drain 310.

The silicide 330 may improve the interface characteristics between thesource/drain 310 and the contact 350. The silicide 330 may be formedinside the source/drain 310 to be in direct contact with the contact350.

Referring to FIG. 3, the semiconductor device according to exemplaryembodiments of the present inventive concept may include a fieldinsulating film 200 formed in a shape of a brace (or curly bracket)(e.g., }) in which an upper surface thereof is recessed toward thesubstrate 100. Such a brace (or curly bracket) shape is shown, forexample, in FIG. 3. For example, the brace (or curly bracket) shape mayinclude curved portions that meet at an indent (or recess) toward thesubstrate 100. According to exemplary embodiments, the curved portionsmay be symmetrical with respect to the indent (or recess) as shown, forexample, in FIG. 3, or may be asymmetrical with respect to the indent(or recess) as shown, for example, in FIG. 8.

The field insulating film 200 which fills the shallow trench ST1 formedbetween the first fin F1 and the second fin F2, or the field insulatingfilm 200 which fills the shallow trench ST1 formed between the secondfin F2 and the third fin F3, may have a lowest height at about thecenter in the first direction D1 in which the first, second and thirdfins F1, F2 and F3 are spaced part from each other. In this case, theheight refers to a distance from the upper surface of the substrate 100in the third direction D3 except the first, second and third fins F1, F2and F3. As illustrated in FIG. 3, the field insulating film 200 mayinclude a first portion P1 including the center of the shallow trenchST1, and a second portion P2 and a third portion P3 formed sequentiallyfrom the center in the first direction D1. For example, the secondportion P2 may be adjacent to the first portion P1, and the thirdportion P3 may be adjacent to the second portion P2 and to a side wallof the shallow trench ST1. The first portion P1, the second portion P2and the third portion P3 have a first height H1, a second height H2 anda third height H3, respectively, from the upper surface of the substrate100. The second height H2 may be higher/greater than the first heightH1, and the third height H3 may be higher/greater than the second heightH2. Thus, among the first height H1, the second height H2, and the thirdheight H3, the first height H1 may be lowest/smallest.

According to exemplary embodiments, the upper surface of the fieldinsulating film 200 which fills the shallow trench ST1 may have aninflection point. According to exemplary embodiments, the upper surfaceof the field insulating film 200 may have three or more inflectionpoints. As illustrated in FIG. 3, the upper surface of the fieldinsulating film 200 according to an exemplary embodiment of the presentinventive concept may have a first inflection point IP1, a secondinflection point IP2, a third inflection point IP3, and a fourthinflection point IP4. In addition, the height from the upper surface ofthe substrate 100 to the upper surface of the field insulating film 200may be lowest in a region between the second inflection point IP2 andthe third inflection point IP3.

Referring to FIG. 4, the semiconductor device according to exemplaryembodiments of the present inventive concept may be formed such that aslope formed by the first direction D1 in which the first fin F1 and thesecond fin F2 are spaced apart from each other and the upper surface ofthe field insulating film 200 is not uniform. For example, the slopeformed by the first direction D1 and the upper surface of the fieldinsulating film 200 may gradually decrease and then increase from thecenter of the upper surface of the field insulating film 200 toward theside wall of the first fin F1 or the second fin F2. As illustrated, thefield insulating film 200 may include regions in which the slopes formedwith the first direction D1 are a first slope θ1, a second slope θ2 anda third slope θ3, respectively. The first slope θ1, the second slope θ2and the third slope θ3 may be the slopes of the regions included in thefirst portion P1, the second portion P2 and the third portion P3 of FIG.3, respectively. According to exemplary embodiments, the first slope θ1may be greater than the second slope θ2, and the third slope θ3 may begreater than the second slope θ2. The signs of the first, second andthird slopes θ1, θ2 and θ3 are the same. Thus, in exemplary embodiments,a height from the substrate 100 to the upper surface of the fieldinsulating film 200 is not uniform.

Referring to FIG. 5, the semiconductor device according to exemplaryembodiments of the present inventive concept may further include a gatestructure 400 which is formed in some parts of the upper surface of thefield insulating film 200 and the upper surfaces and the side surfacesof the first, second and third fins F1, F2 and F3, and extends in thefirst direction D1. The gate structure 400 may include the gateinsulating film 410 and the gate electrode 420, and a lower surface ofthe gate insulating film 410 and a lower surface of the gate electrode420 may be formed in a shape of a brace. The first fin F1, the secondfin F2 and the third fin F3 may penetrate the gate structure 400.

For example, the lower surface of the gate structure 400 may correspondto the shape of the upper surface of the field insulating film 200described above. For example, the lower surface of the gate structure400 may be formed in the shape of the brace, and the height of thecentral portion of the lower surface of the gate structure 400 from thesubstrate 100 may be the lowest relative to other portions of the lowersurface of the gate structure 400. Further, the slope formed by thelower surface of the gate structure 400 with the first direction D1 maygradually decrease and then increase from the center toward the sidesurfaces of the first, second and third fins F1, F2 and F3.

Referring to FIG. 6, the semiconductor device according to exemplaryembodiments of the present inventive concept may include a gatestructure 400 extending in the first direction D1, a plurality ofactivation patterns AP1, AP2 and AP3 penetrating the gate structure 400,extending in the second direction D2 and separated in the firstdirection D1, a shallow trench ST1 formed between the plurality ofactivation patterns AP1, AP2 and AP3, and a field insulating film 200which fills at least a part of the shallow trench ST1 and is formed inthe shape of the brace recessed toward the substrate 100. For example,according to exemplary embodiments, the activation patterns AP1, AP2 andAP3 may be implemented as a nanosheet element.

According to an exemplary embodiment as illustrated in FIG. 6, theshallow trench ST1 formed between the first, second and third activationpatterns AP1, AP2 and AP3 may be the same as the shallow trench ST1formed between the first, second and third fins F1, F2 and F3 of FIG. 2.

Each of the activation patterns AP1, AP2, and AP3 may include an upperpattern in which a periphery is surrounded by the gate structure 400,and a lower pattern that is spaced apart from the upper pattern andprotrudes from the substrate 100.

Although FIG. 6 shows that the number of activation patterns AP1, AP2,and AP3 in which the periphery is surrounded by the gate structure 400is two for each of the activation patterns AP1, AP2, and AP3, exemplaryembodiments of the present inventive concept are not limited thereto.For example, in exemplary embodiments, the number of activation patternsAP1, AP2, and AP3 in which the periphery is surrounded by the gatestructure 400 may be one or may be three or more.

Referring to FIG. 7, a semiconductor device according to exemplaryembodiments of the present inventive concept may include a gatestructure 400, a field insulating film 200, and a first interlayerinsulating film 300 having different heights in the second direction D2.In the description herein, it is assumed that the C-C′ cross section isa region included in the first portion P1 of FIG. 3 and the D-D′ crosssection is a region included in the second portion P2 of FIG. 3.

The height of the field insulating film 200 in the C-C′ cross section isa first height H1, the height of the field insulating film 200 in theD-D′ cross section is a second height H2, and as described above, thesecond height H2 is formed to be higher than the first height H1. Thus,the formed heights of the lower surfaces of the gate structure 400 andthe spacer film 430 formed on the field insulating film 200 may bedifferent from each other. For example, the heights in the thirddirection D3 of the lower surfaces of the gate structure 400 and thespacer film 430 in the C-C′ cross section are formed to be lower thanthe heights in the third direction D3 of the lower surfaces of the gatestructure 400 and the spacer film 430 in the D-D′ cross section. Theheights of the lower surfaces of the gate structure 400 and the spacerfilm 430 refer to the height from the upper surface of the substrate 100in the third direction D3.

The first interlayer insulating film 300, the gate insulating film 410,the gate electrode 420 and the spacer film 430 have upper surfaces ofthe same plane through a planarization process, and the secondinterlayer insulating film 500 is formed on the upper surfaces of thefirst interlayer insulating film 300, the gate insulating film 410, thegate electrode 420 and the spacer film 430. The heights of the gatestructure 400 and the first interlayer insulating film 300 in the thirddirection D3 may also be different between the C-C′ cross section andthe D-D′ cross section. For example, the lower surfaces of the gatestructure 400 and the first interlayer insulating film 300 of the C-C′cross section may have heights lower than those of the lower surfaces ofthe gate structure 400 and the first interlayer insulating film 300 ofthe D-D′ cross section, and the heights of the gate structure 400 andthe first interlayer insulating film 300 of the C-C′ cross section maybe greater than the heights of the gate structure 400 and the firstinterlayer insulating film 300 of the D-D′ cross section.

In a semiconductor device according to exemplary embodiments of thepresent inventive concept, by forming a plurality of segregation layersusing multiple atomic layer deposition (ALD) cycles and an inhibitorplasma, the deposition at the upper end portion of shallow trench ST1 isselectively suppressed, and the deposition at the lower end portion ofthe shallow trench ST1 is suppressed to be less than the upper endportion or is not suppressed. Thus, a bottom-up fill of the fieldinsulating film 200 may be improved, and an occurrence of voids or seamsmay be minimized or reduced. A method for manufacturing a semiconductordevice according to an exemplary embodiment of the present inventiveconcept using the ALD cycle and the inhibitor plasma will be describedlater with reference to FIGS. 13 through 21.

FIG. 8 is a cross-sectional view illustrating a semiconductor deviceaccording to exemplary embodiments of the present inventive concept.FIG. 8 is a cross-sectional view taken along line A-A′ of FIG. 1according to exemplary embodiments of the present inventive concept.

Referring to FIG. 8, according to exemplary embodiments, the uppersurface of a field insulating film 210 may be formed asymmetrically inthe first direction D1. As illustrated, in exemplary embodiments, aportion having the smallest height from the upper surface of thesubstrate 100 to the upper surface of the field insulating film 210 isnot the central portion of the field insulating film 210 in the firstdirection D1. For example, according to exemplary embodiments, theheight of the second portion P2 or the third portion P3 other than thefirst portion P1 of FIG. 3 may be the lowest relative to the otherportions.

In such a case, the slope formed by the upper surface of the fieldinsulating film 210 with the first direction D1 may gradually decreaseand then increase toward the side walls of the fins adjacent to eachother on the basis of the portion having the lowest height.

The upper surface of the field insulating film 210 which fills theshallow trench ST1 may have four inflection points, and may have twoinflection points on both sides on the basis of the portion having thelowest height.

FIGS. 9 and 10 are cross-sectional views illustrating a semiconductordevice according to exemplary embodiments of the present inventiveconcept. FIG. 9 is a cross-sectional view taken along line A-A′ of FIG.1 according to exemplary embodiments of the present inventive concept,and FIG. 10 is a cross-sectional view taken along line B-B′ of FIG. 1according to exemplary embodiments of the present inventive concept.

Referring to FIGS. 9 and 10, according to exemplary embodiments, thelower surface of a field insulating film 220 may be formed in a shaperecessed in an opposite direction of the substrate 100. For example, thelower surface of the shallow trench ST1 is not formed to besubstantially parallel to the first direction D1 or the second directionD2, and at least a part of the lower surface of the shallow trench ST1may be formed in a shape recessed toward the upper surface of the fieldinsulating film 220. As a result, the lower surface of the fieldinsulating film 220 may be formed in a shape recessed in the oppositedirection of the substrate 100 in the third direction D3.

FIG. 11 is a layout view illustrating a semiconductor device accordingto exemplary embodiments of the present inventive concept. FIG. 12 is across-sectional view taken along line E-E′ of FIG. 11 according toexemplary embodiments of the present inventive concept.

Referring to FIGS. 11 and 12, a semiconductor device according toexemplary embodiments of the present inventive concept may furtherinclude a first shallow trench ST1, a second shallow trench ST2, aprotrusion structure PS, and a deep trench DT. The first shallow trenchST1 is formed between the first and second fins F1 and F2, and thesecond shallow trench ST2 is formed between the second fin F2, theprotrusion structure PS and the deep trench DT. The first shallow trenchST1 may have the same shape as the shallow trench ST1 described abovewith reference to FIGS. 2 through 7. The protrusion structure PS is aresidue in which the existing fin structure remains unremoved, and thus,the protrusion structure PS may have a shape different from the firstand second fins F1 and F2.

The protrusion structure PS may protrude from the bottom of the secondshallow trench ST2, and may be lower than the upper surface of a fieldinsulating film 230. As illustrated, the protrusion structure PS may belocated at a boundary between the second shallow trench ST2 and the deeptrench DT.

According to exemplary embodiments, the deep trench DT may be deeperthan the first and second shallow trenches ST1 and ST2. The deep trenchDT is directly connected to the second shallow trench ST2. Since thedepth of the deep trench DT is deeper than the depth of the secondshallow trench ST2, a step may be formed on the bottom surface of theportion by which both trenches are connected.

The side surface of the deep trench DT may be in contact with the fieldinsulating film 230 and the protrusion structure PS. The uppermost partof the deep trench DT may be the same as the heights of some parts ofthe uppermost surfaces or the upper surfaces of the field insulatingfilms 200 and 230.

A deep trench insulating film 240 may fill the deep trench DT. The deeptrench insulating film 240 may include, for example, silicon oxide.

The upper surface of the deep trench insulating film 240 may be lowerthan the upper surfaces of the field insulating films 200 and 230.Accordingly, the upper surface of the deep trench insulating film 240may be lower than the uppermost part of the deep trench DT.

Accordingly, the deep trench DT may include a portion that is in contactwith the deep trench insulating film 240, and a portion exposed by thedeep trench insulating film 240.

According to exemplary embodiments, the segregation layer (SL1 of FIGS.16 to 21) may be formed on both side walls and the upper surfaces of thefirst and second fins F1 and F2, the lower surface of the first shallowtrench ST1, both side walls and the lower surface of the second shallowtrench ST2, and the surface of the protrusion structure PS. Thesegregation layer SL1 may also be formed on both side walls and thelower surface of the deep trench DT.

FIGS. 13 to 21 are intermediate stage diagrams illustrating a method formanufacturing a semiconductor device according to exemplary embodimentsof the present inventive concept. FIGS. 14 to 21 are cross-sectionalviews taken along line F-F′ of FIG. 21. Hereinafter, a semiconductordevices according to exemplary embodiments of the present inventiveconcept will be described with reference to FIGS. 13 to 21. Forconvenience of explanation, a further description of elements andaspects previously described may be omitted or simplified herein.

First, referring to FIGS. 13 and 14, first, second and third masks M1,M2 and M3 are formed on the substrate 100.

The substrate 100 may be made of one or more semiconductor materialsincluding, for example, Si, Ge, SiGe, GaP, GaAs, SiC, SiGeC, InAs andInP. Alternatively, a silicon on insulator (SOI) substrate may be used.

The first through third masks M1 through M3 may extend in the seconddirection D2 and may be spaced apart from each other in the firstdirection D1. The first through third masks M1 through M3 may besequentially disposed in the first direction D1.

Although FIGS. 13 and 14 illustrate three masks M1 through M3, exemplaryembodiments of the present inventive concept are not limited thereto.For example, the number of masks may be varied according to exemplaryembodiments. Further, since FIGS. 15 through 21 are cross-sections takenalong line F-F′, which includes the first and second masks M1 and M2 butnot the third mask M3, FIGS. 15 through 21 illustrate the first andsecond masks M1 and M2 but not the third mask M3.

Subsequently, referring to FIG. 15, the substrate 100 is etched usingthe first and second masks M1 and M2 as masks.

As the substrate 100 is etched, the first and second fins F1 and F2 andthe shallow trench ST1 may be formed.

For example, the shallow trench ST1 may be defined by the first fin F1and the second fin F2.

Subsequently, referring to FIG. 16, the first segregation layer SL1 maybe formed on the lower surface of the shallow trench ST1, and the sidewalls and the upper surfaces of the first and second fins F1 and F2.Hereinafter, the side walls adjacent to each other among the side wallsof each of the first fin F1 and the second fin F2 will be described.However, it will be understood that this description may be equallyapplied to the opposite side wall thereof. The side walls of the shallowtrench ST1 may refer to the side walls adjacent to each other among theside walls of the first and second fins F1 and F2. In addition, althoughthe first and second masks M1 and M2 are illustrated as being removed,according to an exemplary embodiment, the first and second masks M1 andM2 may not be removed, and the first and second masks M1 and M2 may beremoved after an additional process is performed.

According to exemplary embodiments, the side walls of the shallow trenchST1 may be divided into a first trench portion TP1 and a second trenchportion TP2. The first trench portion TP1 may be a region having ahigher height from the substrate 100 than the second trench portion TP2.In this case, the height refers to the height from the upper surface ofthe substrate 100 in the third direction D3. In addition, the first andsecond trench portions TP1 and TP2 may be divided on the basis of thecenter in the third direction D3 of both side walls of the shallowtrench ST1. However, exemplary embodiments are not limited thereto. Forexample, in exemplary embodiments, the first and second trench portionsTP1 and TP2 may be divided on the basis of any point. Further, althoughFIG. 16 illustrates that the side walls are divided into two parts,exemplary embodiments are not limited thereto, and the side walls may bedivided into, for example, three or more parts.

According to exemplary embodiments, the first segregation layer SL1 maybe formed by exposing the first and second fins F1 and F2 and thesubstrate 100 to an inhibitor plasma. The inhibitor plasma may create apassivated surface and may increase a nucleation wall of the depositedfield insulating film. When the inhibitor plasma interacts with thematerial forming the field insulating film 200 in the shallow trenchST1, the lower part (e.g., the second trench portion TP2) of the shallowtrench ST1 may be subjected to less plasma treatment than the upper part(e.g., the first trench portion TP1) of the shallow trench due to ashadowing effect of a geometrical structure. For example, inhibitorplasma treatment may be performed at the first trench portion TP1 morethan at the second trench portion TP2.

According to exemplary embodiments, the first segregation layer SL1 maybe formed by exposing the first fin F1, the second fin F2 and thesubstrate 100 to the inhibitor plasma during a first section.

According to exemplary embodiments, molecular nitrogen (N₂) may be usedas a source gas for the inhibitor plasma. As another example, the sourcegas of the inhibitor plasma may include at least one of, for example,molecular nitrogen (N₂), argon (Ar), helium (He), molecular hydrogen(H₂), ammonia (NH₃) or a combination thereof.

According to exemplary embodiments, the upper parts of the first andsecond fins F1 and F2 may be subjected to more plasma treatment than thesecond trench portion TP2. According to an exemplary embodiment, theupper parts of the first and second fins F1 and F2 may be subjected tothe same plasma treatment as the first trench portion TP1.

According to exemplary embodiments, the lower surface of the shallowtrench ST1 may be subjected to the same or less plasma treatment thanthe second trench portion TP2. According to an exemplary embodiment, theplasma treatment may not be performed on the lower surface of theshallow trench ST1.

Subsequently, referring to FIG. 17, a first atomic layer deposition(ALD) cycle may be performed on the first segregation layer SL1. Forexample, the field insulating film 200 may be formed on the firstsegregation layer SL1. As illustrated, the field insulating film 200 maybe thicker on the second trench portion TP2 of the shallow trench ST1and the lower surface of the shallow trench ST1 in which the plasmatreatment is not performed or the relatively less low plasma treatmentis performed, than on the upper surfaces of the first and second fins F1and F2 and the first trench portion TP1 of the shallow trench ST1 inwhich more plasma treatment is performed.

In describing exemplary embodiments of the present inventive concept, itis described that the segregation layer SL1 is formed, e.g., theinhibitor plasma treatment is performed, prior to performing the ALDcycle for deposition of the field insulating film 200. However,exemplary embodiments are not limited thereto. For example, in exemplaryembodiments, the segregation layer SL1 is not formed prior to performingthe first ALD cycle (or deposition of the first field insulating film200), and the segregation layer SL1 may be formed after at least one ALDcycle is performed.

Subsequently, referring to FIG. 18, a second segregation layer SL2 maybe formed on the field insulating film 200.

According to exemplary embodiments, both side walls of the fieldinsulating film 200 formed between the first and second fins F1 and F2may be divided into a third trench portion TP3 and a fourth trenchportion TP4. The third trench portion TP3 may be a region having ahigher height from the substrate 100 than the fourth trench portion TP4.The third and fourth trench portions TP3 and TP4 may be divided on thebasis of the center in the third direction D3 of the region of theshallow trench ST1 in which the field insulating film 200 is not formed.However, exemplary embodiments of the present inventive concept are notlimited thereto, and the third and fourth trench portions TP3 and TP4may be divided on the basis of any point. Further, although FIG. 18illustrates that the third and fourth trench portions TP3 and TP4 aredivided into two parts, the third and fourth trench portions TP3 and TP4may be divided into, for example, three or more parts.

According to exemplary embodiments, the second segregation layer SL2 maybe formed by exposing the field insulating film 200 to an inhibitorplasma. The inhibitor plasma may generate a passivated surface andincrease the nucleation wall of the deposited field insulating film.When the inhibitor plasma interacts with the material forming the fieldinsulating film in the shallow trench ST1, the lower part (e.g., thefourth trench portion TP4) of the shallow trench ST1 may be subjected toless plasma treatment than the upper part (e.g., the third trenchportion TP3) of the shallow trench ST1 due to the shadowing effect ofthe geometrical structure. For example, inhibitor plasma treatment maybe performed in the third trench portion TP3 more than in the fourthtrench portion TP4.

According to exemplary embodiments, the second segregation layer SL2 maybe formed by exposing the field insulating film 200 to the inhibitorplasma during a second section. According to exemplary embodiments, thesecond section may be the same as or different from the first section.For example, the time during which the inhibitor plasma is exposed tothe substrate 100 or the field insulating film 200 may be appliedequally or differently for each cycle.

Referring to FIG. 19, a second ALD cycle may be performed on the secondsegregation layer SL2. For example, the field insulating film 200 may beformed on the second segregation layer SL2. As illustrated, the fieldinsulating film 200 may be thicker on the fourth trench portion TP4 andthe lower surface of the shallow trench ST1 in which the plasmatreatment is not performed or relatively less plasma treatment isperformed, than on the upper surfaces of the first and second fins F1and F2 and the third trench portion TP3 on which more plasma treatmentis performed.

Referring to FIG. 20, a third segregation layer SL3 may be formed on thefield insulating film 200.

According to exemplary embodiments, both side walls of the fieldinsulating film 200 formed between the first and second fins F1 and F2may be divided into a fifth trench portion TP5 and a sixth trenchportion TP6. The fifth trench portion TP5 may be a region having ahigher height from the substrate 100 than the sixth trench portion TP6.Further, the fifth and sixth trench portions TP5 and TP6 may be dividedon the basis of the center in the third direction D3 of the region ofthe shallow trench ST1 in which the field insulating film 200 is notformed. However, exemplary embodiments are not limited thereto. Forexample, in exemplary embodiments, the fifth and sixth trench portionsTP5 and TP6 may be divided on the basis of any point. Further, althoughFIG. 20 illustrates that the fifth and sixth trench portions TP5 and TP6are divided into two parts, exemplary embodiments are not limitedthereto, and the fifth and sixth trench portions TP5 and TP6 may bedivided into, for example, three or more parts.

According to exemplary embodiments, the third segregation layer SL3 maybe formed by exposing the field insulating film 200 to the inhibitorplasma. The inhibitor plasma may generate a passivated surface andincrease the nucleation wall of the deposited field insulating film.When the inhibitor plasma interacts with the material forming the fieldinsulating film in the shallow trench ST1, the lower part (e.g., thesixth trench portion TP6) of the shallow trench ST1 may be subjected toless plasma treatment than the upper part (e.g., the fifth trenchportion TP6) of the shallow trench ST1 due to the shadowing effect ofthe geometrical structure. For example, more inhibitor plasma treatmentmay be performed on the fifth trench portion TP5 than on the sixthtrench portion TP6.

According to exemplary embodiments, the third segregation layer SL3 maybe formed by exposing the field insulating film 200 to the inhibitorplasma during a third section. According to exemplary embodiments, thethird section may be the same as or different from the first and secondsections. For example, the time during which the inhibitor plasma isexposed to the substrate 100 or the field insulating film 200 may beapplied equally or differently for each cycle.

Referring to FIG. 21, by performing the third ALD cycle, the fieldinsulating film 200 may fill the shallow trench ST1. Thereafter, theupper surfaces of the first and second fins F1 and F2 may be exposedthrough a planarization process. Although the field insulating film 200is illustrated as filling the shallow trench ST1 through three ALDcycles as an example, the number of times of performing the ALD cycle isnot limited thereto. Although the segregation layer is formed betweeneach ALD cycle, exemplary embodiments are not limited thereto.

According to an exemplary embodiment, the described process may beperformed without removing the first and second masks M1 and M2. In thiscase, the upper surfaces of the first and second masks M1 and M2 may beexposed through the planarization process.

As illustrated, according to an exemplary embodiment of the presentinventive concept, by forming a plurality of segregation layers SL1, SL2and SL3 using a plurality of ALD cycles and the inhibitor plasma, thedeposition in the upper end portion of the shallow trench ST1 isselectively suppressed, and the deposition is suppressed to be less (orproceeds without being suppressed) in the lower end portion of theshallow trench ST1. Thus, the bottom-up fill of the field insulatingfilm 200 may be improved and the occurrence of a void or seam may beminimized or reduced.

The planarization process may be, for example, a chemical mechanicalpolish (CMP) process. The field insulating film 200 may be separatedinto the field insulating film defined by the plurality of fins throughthe planarization process.

Thereafter, a part of the upper part of the field insulating film 200may be removed by an etching process. Therefore, as described above withreference to FIGS. 1 to 7, the field insulating film 200 in which theupper surface is formed in a shape of a brace may be formed.

FIGS. 22 to 28 are diagrams provided to describe a semiconductor deviceaccording to exemplary embodiments of the present inventive concept.FIGS. 23, 25 and 27 are cross-sectional views taken along lines G-G′,H-H′ and J-J′ of FIG. 22, respectively, according to exemplaryembodiments of the present inventive concept. FIG. 24 is an enlargedview of area Z of FIG. 23 according to exemplary embodiments of thepresent inventive concept. FIG. 26 is an enlarged view of area W of FIG.25 according to exemplary embodiments of the present inventive concept.FIG. 28 is an enlarged view of area V of FIG. 27 according to exemplaryembodiments of the present inventive concept. For convenience ofillustration, FIGS. 24, 26 and 28 do not show gate insulating films 610,710 and 810 and gate electrodes 620, 720 and 820, respectively.

Referring to FIGS. 22 to 28, the semiconductor device according toexemplary embodiments may include a first field insulating film 550, asecond field insulating film 560, and a third field insulating film 570.

The substrate 100 may include a first region I, a second region II, anda third region III. As an example, the first region I, the second regionII, and the third region III may be regions that perform functionsdifferent from each other. As another example, two regions among thefirst region I, the second region II, and the third region III may beregions that perform the same function, and the other region may be aregion that performs another function. As still another example, thefirst region I, the second region II, and the third region III may beregions that perform the same function.

A first lower pattern BP1 and a second lower pattern BP2 may be disposedin the first region I of the substrate. Each of the first lower patternBP1 and the second lower pattern BP2 may extend lengthwise in a fourthdirection D4. The first lower pattern BP1 and the second lower patternBP2 may be separated by a third shallow trench ST3. On the basis of anupper surface of the first lower pattern BP1 and an upper surface of thesecond lower pattern BP2, the third shallow trench ST3 may have a firstwidth W1 in a fifth direction D5. A first upper pattern UP1 may bedisposed on the first lower pattern BP1 and spaced apart from the firstlower pattern BP1. A second upper pattern UP2 may be disposed on thesecond lower pattern BP2 and spaced apart from the second lower patternBP2. The first field insulating film 550 may fill at least part of thethird shallow trench ST3.

The first gate electrode 620 and the first gate insulating film 610 maybe disposed on the first field insulating film 550, the first lowerpattern BP1, and the second lower pattern BP2. The first gate insulatingfilm 610 may wrap around the first upper pattern UP1 and the secondupper pattern UP2. The first gate electrode 620 is formed on the firstgate insulating film 610 and may wrap around the first upper pattern UP1and the second upper pattern UP2. The first gate electrode 620 extendsin the fifth direction D5 and may intersect the first lower pattern BP1and the second lower pattern BP2. Unlike the illustrated example, thefirst lower pattern BP1 and the second lower pattern BP2 may intersectthe gate electrodes separated from each other according to exemplaryembodiments.

A third lower pattern BP3 and a fourth lower pattern BP4 may be disposedin the second region II of the substrate. Each of the third lowerpattern BP3 and the fourth lower pattern BP4 may extend lengthwise in asixth direction D6. The third lower pattern BP3 and the fourth lowerpattern BP4 may be separated by a fourth shallow trench ST4. On thebasis of an upper surface of the third lower pattern BP3 and an uppersurface of the fourth lower pattern BP4, the fourth shallow trench ST4may have a second width W2 in a seventh direction D7. A third upperpattern UP3 is disposed on the third lower pattern BP3 and may be spacedpart from the third lower pattern BP3. A fourth upper pattern UP4 isdisposed on the fourth lower pattern BP4 and may be spaced apart fromthe fourth lower pattern BP4. The second field insulating film 560 mayfill at least part of the fourth shallow trench ST4.

The second gate electrode 720 and the second gate insulating film 710may be disposed on the second field insulating film 560, the third lowerpattern BP3, and the fourth lower pattern BP4. The second gateinsulating film 710 may wrap around the third upper pattern UP3 and thefourth upper pattern UP4. The second gate electrode 720 is formed on thesecond gate insulating film 710 and may wrap around the third upperpattern UP3 and the fourth upper pattern UP4. The second gate electrode720 extends in the seventh direction D7 and may intersect the thirdlower pattern BP3 and the fourth lower pattern BP4. Unlike theillustrated example, the third lower pattern BP3 and the fourth lowerpattern BP4 may intersect the gate electrodes separated from each otheraccording to exemplary embodiments.

A fifth lower pattern BP5 and a sixth lower pattern BP6 may be disposedin the third region III of the substrate. Each of the fifth lowerpattern BP5 and the sixth lower pattern BP6 may extend lengthwise in aneighth direction D8. The fifth lower pattern BP5 and the sixth lowerpattern BP6 may be separated by a fifth shallow trench ST5. On the basisof an upper surface of the fifth lower pattern BP5 and an upper surfaceof the sixth lower pattern BP6, the fifth shallow trench ST5 may have athird width W3 in a ninth direction D9. A fifth upper pattern UP5 isdisposed on the fifth lower pattern BP5 and may be spaced part from thefifth lower pattern BP5. A sixth upper pattern UP6 is disposed on thesixth lower pattern BP6 and may be spaced apart from the sixth lowerpattern BP6. The third field insulating film 550 may fill at least apart of the fifth shallow trench ST5.

The third gate electrode 820 and the third gate insulating film 810 maybe disposed on the third field insulating film 570, the fifth lowerpattern BP5, and the sixth lower pattern BP6. The third gate insulatingfilm 810 may wrap around the fifth upper pattern UP5 and the sixth upperpattern UP6. The third gate electrode 820 is formed on the third gateinsulating film 810 and may wrap around the fifth upper pattern UP5 andthe sixth upper pattern UP6. The third gate electrode 820 extends in theninth direction D9 and may intersect the fifth lower pattern BP5 and thesixth lower pattern BP6. Unlike the illustrated example, the fifth lowerpattern BP5 and the sixth lower pattern BP6 may intersect the gateelectrodes separated from each other according to exemplary embodiments.

Unlike the illustrated example, the transistors formed in the first tothird regions I, II, III may be FINFETs according to exemplaryembodiments.

In a semiconductor device according to exemplary embodiments of thepresent inventive concept, the second width W2 is greater than the firstwidth W1 and smaller than the third width W3. The first to third fieldinsulating films 550, 560 and 570 may include, for example, an oxide.

In FIG. 24, an upper surface 550 us of the first field insulating film550 may include a first portion P11 adjacent to the first lower patternBP1, and a second portion P12 adjacent to the second lower pattern BP2.The first portion P11 of the upper surface 550 us of the first fieldinsulating film may be in contact with the second portion P12 of theupper surface 550 us of the first field insulating film 550.

In the first portion P11 of the upper surface 550 us of the first fieldinsulating film 550, a slope of the upper surface 550 us of the firstfield insulating film 550 may decrease as the upper surface 550 usextends away from the first lower pattern BP1. In addition, in thesecond portion P12 of the upper surface 550 us of the first fieldinsulating film 550, a slope of the upper surface 550 us of the firstfield insulating film 550 may decrease as the upper surface 550 usextends away from the second lower pattern BP2.

For example, a slope α at an arbitrary point SP of the first portion P11of the upper surface 550 us of the first field insulating film 550 maybe an angle formed by a tangent between the base line and the arbitrarypoint SP. Here, the base line may be a virtual line that connects theuppermost part of the first lower pattern BP1 and the uppermost part ofthe second lower pattern BP2. With movement from the first lower patternBP1 to the second lower pattern BP2, the slope of the upper surface 550us of the first field insulating film 550 may gradually decrease andthen gradually increase again.

In FIG. 26, an upper surface 560 us of the second field insulating film560 may include a first portion P21 adjacent to the third lower patternBP3, a second portion P22 adjacent to the fourth lower pattern BP4, anda third portion P23 between the first portion P21 and the second portionP22.

In the first portion P21 of the upper surface 560 us of the second fieldinsulating film 560, the slope of the upper surface 560 us of the secondfield insulating film 560 may decrease as the second field insulatingfilm 560 extends away from the third lower pattern BP3. In addition, inthe second portion P22 of the upper surface 560 us of the second fieldinsulating film 560, the slope of the upper surface 560 us of the secondfield insulating film 560 may decrease as the second field insulatingfilm 560 extends away from the fourth lower pattern BP4. In the thirdportion P23 of the upper surface 560 us of the second field insulatingfilm 560, the slope of the upper surface 560 us of the second fieldinsulating film 560 may gradually increase and then may graduallydecrease as the second field insulating film 560 extends away from thethird lower pattern BP3.

For example, the upper surface 560 us of the second field insulatingfilm 560 may have a shape of a brace (}) indented toward the substrate100. The description thereof may be the same as that described abovewith reference to FIGS. 3 and 4.

In FIG. 28, an upper surface 570 us of the third field insulating film570 may include a first portion P31 adjacent to the fifth lower patternBP5, a second portion P32 adjacent to the sixth lower pattern BP6, and athird portion P33 between the first portion P31 and the second portionP32.

In the first portion P31 of the upper surface 570 us of the third fieldinsulating film 570, the slope of the upper surface 570 us of the thirdfield insulating film 570 may decrease as the third field insulatingfilm 570 extends away from the fifth lower pattern BP5. In addition, inthe second portion P32 of the upper surface 570 us of the third fieldinsulating film 570, the slope of the upper surface 570 us of the thirdfield insulating film 570 may decrease as the third field insulatingfilm 570 extends away from the sixth lower pattern BP6. In the thirdportion P33 of the upper surface 570 us of the third field insulatingfilm 570, the slope of the upper surface 570 us of the third fieldinsulating film 570 may be constant. For example, the third portion P33of the upper surface 570 us of the third field insulating film 570 maybe a plane (e.g., the third portion P33 of the upper surface 570 us ofthe third field insulating film 570 may be substantially flat).

FIG. 29 is a diagram provided to describe a semiconductor deviceaccording to exemplary embodiments of the present inventive concept.FIGS. 30 and 31 are diagrams provided to describe a semiconductor deviceaccording to exemplary embodiments of the present inventive concept. Forconvenience of explanation, differences from exemplary embodimentsdescribed with reference to FIGS. 22 to 28 will be primarily described,and a further description of elements and aspects previously describedmay be omitted. FIG. 29 is an enlarged view of area W of FIG. 25according to exemplary embodiments of the present inventive concept, andfor convenience of illustration, does not show the corresponding gateinsulating film and the gate electrode. FIG. 30 is a cross-sectionalview taken along line J-J′ of FIG. 22 according to exemplary embodimentsof the present inventive concept. FIG. 31 is a schematic graph showingthe nitrogen concentration along line A of FIG. 30 according toexemplary embodiments of the present inventive concept.

Referring to FIG. 29, in a semiconductor device according to exemplaryembodiments of the present inventive concept, the first portion P21 ofthe upper surface 560 us of the second field insulating film 560 may bein contact with the second portion P22 of the upper surface 560 us ofthe second field insulating film 560. From the third lower pattern BP3to the fourth lower pattern BP4, the slope of the upper surface 560 usof the second field insulating film 560 may gradually decrease and thenmay gradually increase again.

Referring to FIGS. 30 and 31, in a semiconductor device according toexemplary embodiments of the present inventive concept, the third fieldinsulating film 570 may include at least one or more fourth separationlayers SL4 disposed in the third field insulating film 570.

The fourth separation layer SL4 may extend along the side wall and thebottom surface of the fifth shallow trench ST5. The fourth separationlayer SL4 may include a portion substantially parallel to the uppersurface of the substrate 100, a portion substantially parallel to theside wall of the fifth lower pattern BP5, and a portion substantiallyparallel to the side wall of the sixth lower pattern BP6. In thesemiconductor device according to exemplary embodiments, the fourthseparation layer SL4 is not in contact with the fifth lower pattern BP5and the sixth lower pattern BP6. Each fourth separation layer SL4 may bespaced apart from each other. An oxide may be disposed between adjacentfourth separation layers SL4. The fourth separation layer SL4 may be aportion formed through the inhibitor plasma described with reference toFIGS. 13 to 21. The fourth separation layer SL4 may contain nitrogen. InFIG. 30, two fourth separation layers SL4 are formed. However, exemplaryembodiments of the present inventive concept are not limited thereto.

As an example, the second field insulating film 560 may not include aseparation layer disposed in the second field insulating film 560. Asanother example, the second field insulating film 560 may include theseparation layer disposed in the second field insulating film 560.

The first field insulating film 550 does not include the separationlayer.

FIGS. 32 and 33 are diagrams provided to describe a semiconductor deviceaccording to exemplary embodiments of the present inventive concept. Forconvenience of explanation, differences from exemplary embodimentsdescribed with reference to FIGS. 22 to 28 will be primarily described,and a further description of elements and aspects previously describedmay be omitted. The description of the third region III of FIG. 32 maybe substantially the same as that described with reference to FIGS. 22,27, and 28. In FIG. 32, the second region II of FIG. 22 may be omitted.

Referring to FIGS. 32 and 33, in a semiconductor device according toexemplary embodiments, a fourth fin F4 and a fifth fin F5 spaced apartfrom each other in the fifth direction D5 may be disposed in the firstregion I. A FINFET may be formed in the first region I, and a transistorwhich uses a nanosheet or a nanowire as a channel may be formed in thethird region III.

The upper surface of the first field insulating film 550 disposedbetween the fourth fin F4 and the fifth fin F5 may have, for example, ashape as illustrated in FIG. 24.

In FIG. 27, it is assumed that the fifth shallow trench ST5 has a thirdwidth W3 at the first height on the basis of the bottom surface of thefifth shallow trench ST5. A first width W1 of the third shallow trenchST3 may be a width measured at the first height from the bottom surfaceof the third shallow trench ST3.

FIGS. 34 and 35 are diagrams for explaining the semiconductor deviceaccording to exemplary embodiments of the present inventive concept. Forreference, FIG. 35 is a cross-sectional view taken along the line K-K′of FIG. 34. FIG. 35 shows only lower patterns BP7, BP8 and BP9, a fourthfield insulating film 580, and a fifth field insulating film 590.

Referring to FIGS. 34 and 35, a semiconductor device according toexemplary embodiments of the present inventive concept may include afourth field insulating film 580 and a fifth field insulating film 590.

A seventh lower pattern BP7, an eighth lower pattern BP8, and a ninthlower pattern BP9 may extend lengthwise in a tenth direction D10,respectively. For example, the seventh lower pattern BP7, the eighthlower pattern BP8, and the ninth lower pattern BP9 may be disposed in anSRAM region.

A fourth gate electrode 920_1 and a fourth gate electrode 920_2 mayextend in an eleventh direction D11, respectively. Although the fourthgate electrode 920_1 may intersect the seventh lower pattern BP7, andthe fourth gate electrode 920_2 may intersect the eighth lower patternBP8 and the ninth lower pattern BP9, exemplary embodiments are notlimited thereto. For example, in exemplary embodiments, the fourth gateelectrode 920_1 may intersect the seventh lower pattern BP7 and theeighth lower pattern BP8, and the fourth gate electrode 920_2 mayintersect the ninth lower pattern BP9. Unlike the illustrated example,in exemplary embodiments, the fourth gate electrode 920_1 and the fourthgate electrode 920_2 may be directly connected to each other.

For example, the fourth gate electrode 920_1 and the fourth gateelectrode 920_2 may wrap around at least one or more upper patterns asshown in FIGS. 23, 25 and 27.

The seventh lower pattern BP7 and the eighth lower pattern BP8 may beseparated by the sixth shallow trench ST6. On the basis of the uppersurface of the seventh lower pattern BP7 and the upper surface of theeighth lower pattern BP8, the sixth shallow trench ST6 may have a fourthwidth W4 in the eleventh direction D11. The eighth lower pattern BP8 andthe ninth lower pattern BP9 may be separated by the seventh shallowtrench ST7. On the basis of the upper surface of the eighth lowerpattern BP8 and the upper surface of the ninth lower pattern BP9, theseventh shallow trench ST7 may have a fifth width W5 in the eleventhdirection D11. In a semiconductor device according to exemplaryembodiments of the present inventive concept, the fourth width W4 isgreater than the fifth width W5. The fourth field insulating film 580may fill at least a part of the sixth shallow trench ST6. The fifthfield insulating film 590 may fill at least a part of the seventhshallow trench ST7.

In a semiconductor device according to exemplary embodiments of thepresent inventive concept, the upper surface of the fourth fieldinsulating film 580 may have a shape of the upper surface 570 us of thethird field insulating film 570 described with reference to FIG. 28. Theupper surface of the fifth field insulating film 590 may have a shape ofthe upper surface 550 us of the first field insulating film 550described with reference to FIG. 24 or a shape of the upper surface 560us of the second field insulating film 560 described with reference toFIG. 29.

FIGS. 36 to 40 are intermediate stage diagrams provided to describe amethod of manufacturing a semiconductor device according to exemplaryembodiments of the present inventive concept.

Referring to FIG. 36, a first pre-pattern PF1, a second pre-pattern PF2,and a third pre-pattern PF3 may be formed on the substrate 100.

The first pre-pattern PF1 may be separated by a third shallow trenchST3′. The second pre-pattern PF2 may be separated by a fourth shallowtrench ST4′. The third pre-pattern PF3 may be separated by a fifthshallow trench ST5′. Each of the first to third pre-patterns PF1, PF2and PF3 may include a channel pattern CP and a dummy pattern DP. Thechannel pattern CP may be the upper pattern of FIGS. 23, 25 and 27.

Referring to FIG. 37, a first pre-field insulating film 550_1 is formedon the substrate 100. The first pre-field insulating film 550_1 mayinclude an oxide.

The first pre-field insulating film 550_1 may entirely fill the thirdshallow trench ST3′. The first pre-field insulating film 550_1 may filla part of the fourth and fifth shallow trenches ST4′ and ST5′. The firstpre-field insulating film 550_1 may be formed by, for example, aflowable CVD (FCVD) method.

Referring to FIG. 38, a second pre-field insulating film 550_2 may beformed on the first pre-field insulating film 550_1. The secondpre-field insulating film 550_2 may include an oxide. The secondpre-field insulating film 550_2 may fill the rest of the fourth andfifth shallow trenches ST4′ and ST5′. The third pre-field insulatingfilm 550_2 may be formed by the method described with reference to FIGS.13 to 21.

Referring to FIG. 39, the upper surfaces of the first to thirdpre-patterns PF1, PF2 and PF3 may be exposed, by removing the first andsecond pre-field insulating films 550_1 and 550_2 disposed on the uppersurfaces of the first to third pre-patterns PF1, PF2 and PF3.

Referring to FIG. 40, the first and second pre-field insulating films550_1 and 550_2 may be partially removed in the third to fifth shallowtrenches ST3′, ST4′ and ST5′.

Although it is illustrated that the second pre-field insulating film550_2 does not remain in the fourth shallow trench ST4′, exemplaryembodiments of the present inventive concept are not limited thereto.For example, whether the second pre-field insulating film 550_2 remainsmay vary depending on the degree of the recess of the first and secondpre-field insulating films 550_1 and 550_2. Subsequently, the dummypattern DP may be removed.

While the present inventive concept has been particularly shown anddescribed with reference to the exemplary embodiments thereof, it willbe understood by those of ordinary skill in the art that various changesin form and detail may be made therein without departing from the spiritand scope of the present inventive concept as defined by the followingclaims.

What is claimed is:
 1. A semiconductor device, comprising: a substrate;a first fin; a second fin, wherein the first and second fins are spacedapart from each other in a first direction on the substrate and extendin a second direction intersecting the first direction; a first shallowtrench formed between the first and second fins; and a field insulatingfilm which fills a first part of the first shallow trench and exposes asecond part of the first shallow trench, wherein the field insulatingfilm comprises a first portion, a second portion adjacent to the firstportion, and a third portion adjacent to the second portion and adjacentto a side wall of the first shallow trench, wherein the first portioncomprises a central portion of an upper surface of the field insulatingfilm in the first direction, wherein the upper surface of the fieldinsulating film is in a shape of a brace recessed toward the substrate,wherein a center of the first portion has a convex shape, wherein an endportion of the first portion has a concave shape toward the substrate,and wherein the third portion has a convex shape toward the substrate.2. The semiconductor device of claim 1, wherein a height from an uppersurface of the substrate to the upper surface of the field insulatingfilm is smallest at the first portion.
 3. The semiconductor device ofclaim 1, further comprising: a gate structure extending in the firstdirection on the substrate, wherein each of the first and second finspenetrates the gate structure.
 4. The semiconductor device of claim 1,further comprising: a gate structure formed on the upper surface of thefield insulating film and a part of upper surfaces and side surfaces ofthe first and second fins, and extending in the first direction.
 5. Thesemiconductor device of claim 1, wherein a height from an upper surfaceof the substrate to the second portion is greater than a height from theupper surface of the substrate to the first portion, and a height fromthe upper surface of the substrate to the third portion is greater thanthe height from the upper surface of the substrate to the secondportion.
 6. The semiconductor device of claim 1, wherein a height froman upper surface of the substrate to the upper surface of the fieldinsulating film is not uniform.
 7. The semiconductor device of claim 6,wherein the height from the upper surface of the substrate to the uppersurface of the field insulating film is smallest at the central portionof the upper surface of the field insulating film in the firstdirection.
 8. The semiconductor device of claim 1, further comprising: asegregation layer formed on both side walls and upper surfaces of thefirst and second fins and a lower surface of the first shallow trench.9. The semiconductor device of claim 8, further comprising: a secondshallow trench adjacent to the second fin in the first direction; a deeptrench adjacent to the second shallow trench and having a depth deeperthan the second shallow trench; and a protrusion structure protrudingfrom a bottom of the second shallow trench and lower than the uppersurface of the field insulating film.
 10. The semiconductor device ofclaim 9, wherein the segregation layer is formed on both the side wallsand the upper surfaces of the first and second fins, the lower surfaceof the first shallow trench, both side walls and a lower surface of thesecond shallow trench, and a surface of the protrusion structure.
 11. Asemiconductor device, comprising: a substrate; a first fin; a secondfin, wherein the first and second fins are spaced apart from each otherin a first direction on the substrate and extend in a second directionintersecting the first direction; a first shallow trench formed betweenthe first and second fins; and a field insulating film which fills afirst part of the first shallow trench and exposes a second part of thefirst shallow trench, wherein an upper surface of the field insulatingfilm comprises a first portion, a second portion and a third portionsequentially located from a center of the shallow trench in the firstdirection, wherein a first slope formed by the first portion with thefirst direction is greater than a second slope formed by the secondportion with the first direction, and a third slope formed by the thirdportion with the first direction is greater than the second slope,wherein signs of the first, second and third slopes are the same,wherein the first portion has a concave shape toward the substrate, andwherein the third portion has a convex shape toward the substrate. 12.The semiconductor device of claim 11, wherein a height from an uppersurface of the substrate to the second portion is greater than a heightfrom the upper surface of the substrate to the first portion, and aheight from the upper surface of the substrate to the third portion isgreater than the height from the upper surface of the substrate to thesecond portion.
 13. The semiconductor device of claim 11, furthercomprising: a segregation layer formed on both side walls and uppersurfaces of the first and second fins and a lower surface of the firstshallow trench.
 14. The semiconductor device of claim 13, furthercomprising: a second shallow trench adjacent to the second fin in thefirst direction; a deep trench adjacent to the second shallow trench andhaving a depth deeper than the second shallow trench; and a protrusionstructure protruding from a bottom of the second shallow trench andlower than the upper surface of the field insulating film.
 15. Thesemiconductor device of claim 14, wherein the segregation layer isformed on both the side walls and the upper surfaces of the first andsecond fins, the lower surface of the first shallow trench, both sidewalls and a lower surface of the second shallow trench, and a surface ofthe protrusion structure.
 16. A semiconductor device, comprising: asubstrate; a first fin; a second fin, wherein the first and second finsare spaced apart from each other in a first direction on the substrateand extend in a second direction intersecting the first direction; ashallow trench formed between the first and second fins; and a fieldinsulating film which fills a first part of the shallow trench andexposes a second part of the shallow trench, wherein an upper surface ofthe field insulating film is in a shape having a first inflection pointand a second inflection point sequentially located from a center of theshallow trench in the first direction, wherein the upper surface betweenthe first inflection point and the second inflection point has a concaveshape toward the substrate, and wherein the upper surface between thesecond inflection point and a side wall of the shallow trench has aconvex shape toward the substrate.
 17. The semiconductor device of claim16, wherein the upper surface of the field insulating film is in a shapehaving three or more inflection points.
 18. The semiconductor device ofclaim 17, wherein a height from an upper surface of the substrate to theupper surface of the field insulating film is smallest at a centralportion of the field insulating film in the first direction.
 19. Thesemiconductor device of claim 16, wherein the field insulating filmcomprises a first portion, a second portion and a third portionsequentially formed from a center of the shallow trench in the firstdirection, and a height from an upper surface of the substrate to thesecond portion is greater than a height from the upper surface of thesubstrate to the first portion, and a height from the upper surface ofthe substrate to the third portion is greater than the height from theupper surface of the substrate to the second portion.
 20. Thesemiconductor device of claim 19, wherein a slope formed by the firstportion with the first direction is larger than a slope formed by thesecond portion with the first direction, and a slope formed by the thirdportion with the first direction is larger than a slope formed by thesecond portion with the first direction.